Mill



March 22, 1927.

W. .W. GIBSQN Filed Aug. 25. 1924 MILL 3 Sheets-Shut l I I W II 1. N I" i I I 3;.

Km. N I i u '1 t a? LN I Tl m an I Ill INVENTDR w vz BIBBUN March 22,1927.

w. w. GIBSON MILL 3 Sheets-Sheet 2 Filed Aug. 25. 1924 INVENTDR w w: GIBSON March w. w. mason MILL Filed Aug. 25. 1

3 Shaw-Sheet 3 IN VENT [IR WW GHBSDW Patented Mar. 22, 1927.

WILLIAM WALLACE GIBSON, or ALAMEDA, CALIFORNIA.

MILL.

Application med Aiighst 25, 1924. Serial no. 733,97'2.

inYention relates to improvements in e e e in me' to ;)1"0. 1j v t lticyljinder mi ll in which the cylinders revolve around a .eentral ax le instead of revolving on their own ages, With a result that the eriilshing" elements used in the ylinders: ar c j i higher en 0 9? ev r in cur'izedj paths giv ng a greater 6111 1811111 effeet with less wear on the cylinders and without the tendency oi: the erushingl elememe, to creep, whijeh tendency occurs Where the eylingiers revolve on their own axes.

nether object o t'the invention isto provide a; ninlti eylinder mill of the chart eter deselfibed in Whieh the cylinders are equidi n y' See ed in n we a r ng me about .a oeii'trel agde sothet a, eounterbalene} ing efieetlis provided which will reduce horse power req iiredte effectively operate the niill parts,

and, pe fo ep et e e 1 1 3 e be t; drive gtrr'elngemerit instead of requiring employment of geers, thus making possible an operation of the niill on less power and a esece ti 7 A tnifther' objj is to provide in L mill; of th heractit de c e ah ioref d m n fo hat aut m t cal y en y 10m h e p ive ylin er at a tim l an prev nts clogging or jamming of the feed pessages and an unbalanced oonditionin the 111 111. 2 Th in nt on f r her h t rkone of s objects to, provi 1Q no vel means for auto matieelly classifying the ore, which c1essifieremri'ies overfs'ize materiel which will not pass throrilgh the screen hack to the cylinders o be" reground, By this arrangement the mill be oonsti'ucted ci Sh,,. for ex; ample front 8 to 00 mesh, Without demege or inj u ry to the sereen or ncreasing the cost of constfi etion and operzttwn 011 the 1'11,

Thenlill of: this inventi n in ai iditio'lg to the advantages above enumerated which it provides, is simple (is to construet ion and arrangement; consists of corli paret yely few is comparatively inezgpensive,v arranged; so that \ii'orir or broken parts, may be readily andeasily replaced and is durable and reliable in its operation Withthe above mentioned anctotherobjects in View, the invention consists in the novel construction and combination of parts hereinafter described, illustratedin the afe'} coinpenyin'g drawings, enci'set forth the clainis hereto appended; it being understood is and one of its objects is 4 el he -lee v I f Fig. 1 represents a slde elevation o'f'al rnil l constructed in accordance with the invention.

Fig. 2 represents ai loi g itildinzil seeti'on I View of the mill otthis inventiont Fig. 3 represents a rear el'ewfetion" of" the injll p rmbeing broken away and; other parts. heingfshown in section order to shots? the arrangement and oons'trnetion of the i l m i i H (e t represents gt front elevation ofthe m1. r i

The einbogiir'nent of the invention" inn treted" in detail in the accompanying-drewing s incl ndese central shaft 1, jonrnelebtin suitable befaingsti l on stendar ds 3;, there being pulley 4' fixed to one endof the shtft to provide for operation'of the 1nil1 with at belt driveermngement, not shown. At the other end of the sheit there is provided at right engltllerly extendingl scoo p 5 edztpted to pick up ore from a; hopper; not shown, and convey itthrongh a hollow feed" portion Got the to the distrih'uter 7'. The. see O15 5 is reinotebly fastened es at 8; to the end of the shjgtft. The" portion Got the shift is proyided with internal sei ew threads 9 for fjy'eilitzytingrf the feed" of ore to the (listrihliter'. Thisf s bute in th pres efi em- Pris s a! p t z litylof ret l' y te igif tl'lbes 1 p] of qual length, forined' integtttl e in oonnnunioationKkiith M 1011GitiiGljBOtt The outer ends of'the tubes flai -e provici with flanges l1 Whieh are bolted as at 12 to the ends of apliiifali'ty (it erushing eylindet's 13,1111 the present instance there being tour of such eylintiei s shown. These cylinders, are arranged in an alienate s'ei i'esaronnctthe axle 2, in spaced reletionto one enother'and; to the axleso that the erfrangenientof the cylinders will serve es an effective eoiinterbalance to assi st intheoperetionot the mill. 7 L

Eeeh cylinderis provided with an intake o aening" 14 in registretion" j with one ofthe t be; 1 0 and is also proyidett with the v usual liner 15, having" an opehingf 16. reg isterin'g;-

with the opening 14. The other end of each cylinder is provided with an annular flange 17 bolted onto a grizzly 18 in the form of a circular flat plate, which grizzly extends over the open ends of the several cylinders and is provided with an opening 19 centrally thereof, through which the shaft 1 extends. A flanged collar 20 on the shaft holds the grizzly and shaft in proper assembled relation. Those portions of the grizzly which register with the cylinders are-provided with a series of arcuate openings or slots 21 around. the discharge openings 22, which latter are provided with internal screw threads 23 to urge anintakeof ore. Balls or rods,.or other crushing elements, in the present instance being shown as balls, designated 24, are mounted in each cylinder as is customary in the art.

Attached to the rear face of the grizzly is an angle iron ring 25 to which a circular screen 26 is bolted. A similar ring. 27 is provided for the outer end of the screen. The inner end of the screen abuts the outer face of the grizzly whereas the outer end of the screen is closed by an annular plate 27" bolted to the ring 27. The size of the mesh of this screen depends on the character of the Work to be accomplished by the mill and may be varied in view of the special construction of this invention, for example,

from 8 to 100. y f

It will thus be seen that the mill may be readily and easily disassembled in units or sections so that worn or damaged parts may be readily replaced.

A plurality of classifying members in the form of scoops as shown at 28, are provided in the screen and act automatically to pick up the over-size ore particles within the screen and convey them back to the respective cylinders, there being one classifying scoop for each cylinder. These scoops are closed except where communicated -w1th the openings 23 in the grizzly and at their mouth ends, which latter are elongated and extend for the width or length of the screen so that as the material which does not pass through the screen is carried around the screen it will he picked up in the open ends or mouths 29 of the S000 s and by virtue of the inclined walls 30 of t 1e scoops be gravitated into the openings 22 back to the respective cylinders of the mill, in order to he reground.

. The operation of the mill is as follows: The feed scoop 5 picks up the ore and delivers it into the screw feed portion 6 of the axle, from whence it passes through the distributer tubes 10 into the respective cylinders 13. The tubes 10 are so arranged that like quantities of the ore are delivered to each cylinder and the balanced arrangement will therefore be maintained in the mill. As the ore is delivered through the openings 14;

and 16 into the cylinders, on rotation of the mill, the crushing elements 24 will be car ried up and tossed over in curved paths so as to have an effective crushing action on the ore, much more so than is the case in millswhere the cylinders turn about their own axes, this being particularly due to the fact that the crushing elements will not tend to creep and will be given a greater degree of movement. This arrangement therefore provides for a quicker and more effective crushing of the ore with less wear on the mill parts than is possible with mills having a crushing cylinder rotating on its own axis.

The equal distributionof the ore to the cylinders andbalanced arrangement of the cylinders provides a counterbalancing action which will effect a saving in power required to operate the mill.

As the ore is crushed and fed through the open ends 21 of the grizzly into the screen 26, the finer particles desired will pass through the screen into a suitable container or otherwise collected, as desired. The oversize ore particles, that is, the particles which will not pass through the screen, will be carried around on the inner side of the screen and be picked up by the scoop members 29. These scoop members 29 because of the inclined walls-3O and their positions relative to the screen, will convey the oversize ore particles back through the screw feed opening 22 into the mill, where they will be recrushed. The operation repeating until the ore is crushed to the necessary fineness to screen. This arrangement provides for crushing ore at from 8 to 100 mesh without jamming, puncturing or otherwise damaging the screen, whereas in other mills having peripheral discharge screens, such an arrangement would result in damage to the screens unless classifiers such as provided in this invention were employed.

The re-grinding of the over-size particles as provided in this invention eliminating that objectionable condition known in the art as sliming and insures a product of uniform mesh. By renewing the classifier and screen and substituting a blank end, the mill may thus be connected into an ordinary sliming mill.

' I claim:

1. An ore crushing mill comprising a plurality of crushing cylinders, a shaft around which said cylinders are arranged in equidistantly spaced relation to one another and to the shaft, means for attaching the cylinders to the shaft, means for rotating the shaft, a plurality of crushing members in each of the cylinders, an ore scoop attached 9. An ore crushing mill comprising a plurality of crushing cylinders revolvable about a central axis, means for so mounting said cylinders including a shaft having a holloW 5 feed portion extending into it from one end, an ore scoop connected with and adapted to deliver ore into said feed portion, a plurality of tubes of equal length extending from the feed portion of the shaft to and being in communication with certain ends 10 of the cylinders and a plurality of crushing members in each of the cylinders.

WILLIAM WALLACE GIBSON. 

